Skład izotopowy azotanów w wodach podziemnych Polski

The level of nitrate concentration in groundwater is a measure of the degree of contamination of the environment. However, it says little about the origin of nitrates. Stable isotopes of N and O (δ15 N and δ18 O) can differentiate between manure and chemicalfertilizers. This is the reason for undertaking a study on groundwater with high concentration of nitrates in the national monitoring network to recognize the origin of nitrates. Contrary to expectations, the results suggest that nitrates are derived mostly from manures and less from chemical fertilizers. Further studies are urgently needed.